Nikkei:

As with regular vehicles, owners will generally be liable for accidents that occur while their cars operate autonomously and will be covered by government-mandated automobile insurance. Automakers will only be responsible if there is a clear flaw in the vehicle’s system. Insurers are also expected to develop optional plans now that compulsory coverage requirements are settled.
 
 To help clarify the cause of accidents, self-driving cars will be required to have devices that record such information as location, steering and the operational status of autonomous driving systems.